A weapon must be capable of almost instantaneously firing short bursts against targets which may be particularly fleeting. In order to achieve a high firing rate, which is necessary to hit such a target, use is made either of a multi-tube weapon of the GATLING type, which, however, exhibits the notable drawback of being heavy and bulky, or a weapon with one or two tubes, of the type with a barrel, which is lighter and more compact, but which is of lower performance in terms of the rate of fire than a weapon of the GATLING type.
In an automatic weapon of the barrel type, as described in the document FR-A-2637061 for example, the ammunition feed system consists of a belt composed of a succession of links which each support one round. This belt, stored in an ammunition box, is partially wound over a feed star wheel which interacts with a pick-off device to extract the ammunition from the links of the belt. The ammunition, free from its links, is then led by an insertion star wheel to the chambers of the barrel into which it is progressively inserted in the course of the intermittent rotation of the barrel. The energy source for transferring the ammunition from the belt to the barrel generally consists of a part of the propulsion gases generated by the round fired and which are used to drive the barrel in rotation, this rotational movement being simultaneously transmitted by the insertion star wheel to the feed star wheel by pinions. The empty links of the belt are generally recovered into the ammunition box. Such a recovery of the links constitutes a drawback, especially when the weapon is installed on an aircraft.
One object of the invention is particularly to resolve the problem posed by the ejection of the links of the ammunition belt, by virtue of a feed system of completely different design in which the ammunition rounds are stored in an ammunition box without being linked to one another by any intermediate medium, that is to say that the abovementioned links are purely and simply dispensed with.
An ammunition box or magazine without links is described, for example, in the document EP-A-0 365 145. The ammunition is arranged at the periphery of a rotary unit mounted in a box and interacting with a helical fixed ramp on the inner wall of the box in order to move it axially during rotation of the rotary unit.
However, a feed system which necessarily comprises a drive mechanism for leading the ammunition rounds, one by one, to a weapon loading and firing system poses other problems which are related particularly, on the one hand, to the obtaining of an instantaneous rise in rate of the weapon, having regard to the inertia inherent in the ammunition drive mechanism, and, on the other hand, to the recoil movement of the weapon which must not disturb said ammunition drive mechanism.
These problems which are posed particularly for a medium-calibre weapon are not set out in the document EP-A-0 365 145 which relates to a small-calibre weapon, of the machine pistol type.